Drawing-board structure.



0. B. ULRICH.

DRAWING BOARD STRUCTURE.

APPLICATION FILED $1212.11. 1911. Rmnwnn MAR. 9,1912.

1,1 1 3,263. Patented Oct. 13, 1914.

2 SHEETS-SHEET 1.

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WITNESSES 7 WW wu- ATTO R N EY INVENTOR,

G. B. ULRICH.

DRAWING BOARD STRUCTURE.

RENEWED MAR.9,1912.

Patented Oct. 13, 1914 2 SHEETSSHBET 2.

APPLICATION FILED PEB.11. 1911.

9 4 l 3 I x.

ATTORNEY WITNESSES 4 V a citizen of the United States, residing, at.

CHARLES B. ULRICH, OF HANCOCK, MICHIGAN.

DRAWING-BOARD STRUCTURE.

Specification of Letters Patent.

Patented Oct. 13, 1914.

Application flied February 11 1911, Serial No. 608,059. Renewed March 9,1912. Serial No. 682,757.

T 0 all whom it may concern Be it known that 1, CHARLES B. ULRICH,

Hancock, in the county of Houghton and State of Michigan, have inventeda new and useful Drawing-Board Structure, of which the following is aspecification. This invention has reference to improvements in draftingboards and is designed particularly for use by draftsmen, wherebydrawing paper may be conveniently held in place, tracings may be readilymade, the drawing ink may be caused to rapidly dry, and photographicprints, usually blue prints, may be made without change in the structure. For this purpose there is provided a stand having a suflicientlybroad footing to render it stable, .and mounted on this stand there is abox-like structure having a transparent topwith a marginal frame,whereby drawing paper or tracing cloth may be readily attached and lightmay be produced within the box to shine through the transparent top tofacilitate the making of tracings, while provision is made both for theventilating of the box and for the utiliza tion of the heat of the lightelements to cause the drying of the ink used when such is desired.Furthermore, a presser board is provided, whereby the light emanatingfrom the light producing element/sin the box may. be employed for the.making 'of blue printsor other photographic prints.

The invention will be best understood from a consideration 'ofthe-following detailed description, taken in connection with theaccompanying drawings forming a part of this specification, with theunderstanding, however, that while the showing of the drawings is thatof a practicalembodiment of the invention, the latter is susceptible ofother practical embodiments, and, therefore, is not limited to the exactshowing of the drawlngs. d

In the drawings :r-Figure'1 is a perspective view of' the improveddrafting board structure showing the light box in a partially tiltedposition. Fig. 2 is'a longitudina l central vertical section of thedrafting -board structure. Fig. 3 is a section on the line 3-3 of Fig.2. Fig. 4 is a section on the line 4-4 of'Fig. 3, showing the presserboard for blue printing in place. Fig. 5 is a bottom plan view ofthepresser board, the figure'being broken longitudinally.

Referring to the drawings, there is shown longitudinal strips 5 alsoconstituting braces,

the stand being of comparatively little height but of sufficient basicextent to be very stable.

Connected to one of the longitudinal members of the frame 2, the latterbeing longer than wide, by hinges 6, is a box 7 of invertedfrusto-pyramidal form, although the particular form is not mandatory.The box is open at its lower end, that is the end hinged to the stand 1,and at the upper'endis provided with a rectangular frame 8 provided witha rabbet-9 about its inner edge for the reception of a'sheet '10,preferably of plate glass, but this plate may bemade of othertransparent or translucent material.

At the smaller, lower end of the box 7 there is provided a strip 11.upon which may be mounted light giving elements 12 conventionally shownas ordinary incandescent electric lamps, but, of course, it will beunderstood that this showing is simply indicative, since in thepractical embodiment of .the invention either tungsten or mercuryelectric lamps are to be preferred, the mercury lamps having the highestactinic value, and consequently best adapted for the production of blueprints in the manner which will hereinafter appear, while where the costof the structure is to be considered tungsten will answer, though alonger exposure is needed for blue printing. However, the invention isnot limited to any particular type of light giving element. The lowerend'of the box 7 may be in part supported on cross pieces 13 mounted inthe frame 2, and these cross pieces may also support the strip 11carrying the lamps 12. Secured on one end of the box 7 is 'an electricswitch 14 from which extend conducto the ends of 'the box exteriorthereto, and

each block carries a link 20'by means of a pivot bolt 21, while the end.of the link 20 remote from the pivot bolt is slotted; as indicated at22 for the passage of a screw stud 23 projecting from the poi-respondingend of the frame 1, and this stud is provided with a"wing nut 21 bymeans'of which the link 20 may be clamped in any position of adjustmentto hold the box 7 in any desired degree of tilting.

While two links 20 are shown, it will be understood that unless thestructure be heai y a single link will answer, since the hinges G ferman extended connection with the basic .member 1.

The outer or exposed edge of the glass plate 10 is in the same plane asthe outer surface of the frame 8, and there is therefore provided aplane surface for the reception of drawing paper, a sheet of which isindicated at 25 in Fig. 1, while the frame 8 may be made of somesuitable soft wood adapted for the ready reception of thumb tacks 26,whereby the paper sheet 25 or a sheet of tracingcloth or paper may beheld to the glass plate 10. The frame 8 and the glass plate 10constitute a drawing board of appropriate size with a transparentworking area, and when the lamps 12 are caused to emit light, this lightwill traverse the glass plate 10 and the sheet 25, whether the latter beof drawing or tracing paper or tracing cloth."

In order that the light may be diffused where passing through the glassplate 10, the inner walls of the box may be provided with a lining 27 oflight diffusing material, a lining of magnesium or other such whitematerial, or white paint, or any suitable light reflecting material maybe used. The diffusion of the light may be brought about even moreeffectively by having the glass plate 10 provided witha ground surface.

The lamps 12, of course, emit heat as well as light, and in order thatthe glass plate 10 may not become unduly heated the sides of the box 7,except that side adjacent the operator, are provided with elongatedpassages 28 immediately beneath the corresponding portions of the frame'8. By this means there is produced a draft through the open lower endof the box 7 and the heated air escapes through the openings 28. It isadvisable at times to provide for a heating, of the plate 10 whereby inkbeing used in the making of the drawing will dry more rapidly than'itwould if the plate were not heated. For this purpose the openings 28 maybe partially or wholly closed, and in order that this may be done,slides 29 are provided mounted in guides 30 fast to the correspondingside portions of the box 7 and knobs or handles 31 in the slidesfacilitate the adjustment thereof. By making these slides to fit withsufficient snugness in their guides, they will remain in the position towhich they maybe moved.

By means of the heat generated by the lamps as controlled by the slides29, the ink on a drawing may be made to dry almost as rapidly as it isplaced on the drawing ma terial and the making of the drawing is to thisextent facilitated.

When it is desired to make tracings, the drawing or print is firstplaced upon the glass plate 10 and then the material on which thetracing is to be made is placed in overlying relation to the patternandboth are suitably fastened on the frame 8, or if too small to be securedto the frame 8, may be held to the glass plate either by weights or bysuction fastening devices, and when the lamps 12 are energized the lighttraversing the pattern and the tracing material will bring the patterninto brilliant view. The practical embodiment of the invention hasdemonstrated that the finest lines on a blue print are readily visibleand easily traceable.

The device is also practically adaptable for the making of blue prints,and for this purpose one end of the frame 8 has secured thereto spacedbrackets 32 from each of which projects a pin 33, and there is alsoprovided a presser board 34 of the same or approximately the same areaas the top of the drawing board structure as defined by the frame 8, andthe glass sheet 10. This board has fast thereto at one edge loops oreyes 35 adapted to engage the pins 33. The end of the presser board 34remote from the loops or eyes 35 is provided with swingable arms 36,which are so bent that when pivoted in brackets 37 at the corre spondingend rum presser board the freeends of these arms may be moved intounderriding relation to the corresponding portion of the frame 8, andthese free ends are provided with cam levers 38 designed to engage theunder side of the corresponding portion of the frame 8 to lock thepresser board 34 in clamping relation to the frame 8. The engaging faceof the presser board 34 is covered with a pad 39 of felt or othersuitable material which will compress a sheet of blue print or otherphotographic paper against a tracing or sheet of drawing on the drawingboard in such manner that the printing paper is held in engagement withthe drawing at all points and will be subject to the effect of lightemitted from.

the lamps 12 and a blue print or other photographic print may be made bysuitable exposure to the light of the lamps 12 and the subsequentdeveloping operations incident to the making of such prints. In Fig. 4the sheet of photographic paper is indicated at 40 in overlying relationto a. sheet d1 upon which it is assumed the drawing to be copied hasbeen made.

By making the presser board 34 of suitable material it may be utilizedfor drawing purposes when secured in position on the drawing boardstructure, especially where it is not desired that light or heat betramsmitted through the drawing being made.

The drawing board proper composed of the frame 8 and plate 10 is whenlevel of a height convenient to the person using it when standing, butsometimes the user desires to have the drawin surface at a slant, inwhich case the box is turned on the hinges 6 and secured by the thumbnut or nuts 24 in such slanting position. In either case the recessionof that side of the box 7 toward the operator provides ample knee room,so that the shape of the box contributes not only to the reflection ofthe light from the lamps through the transparent or translucent surface,but to the convenience of the user.

By providing the divergent legs at opposite ends of an extendedsupporting frame,

there is formed a stable support for the light box and drafting surfaceand the brace bar 5 on the side of the frame toward the operatorconstitutes a convenient rest for the foot of the operator whenstanding.

What is claimed is 1. A drafting structure comprising a basic memberhaving an extended top portion, a light-box hinged at one edge of oneend to one edge of the top portion of the basic member, said box beingprovided with a light transmitting working surface at the end thereofremote from that hinged to the basic member, light producing meanslodged within the box for producing light to be transmitted through theworking surface, and holding means between the box and the basic memberfor holding said box with its working surface level or inclined at will.

2. A drafting structure comprising a suitable support, a light boxmounted thereon and open at the end carried by the support,

said light box being provided with a light transmitting working surfaceand with ventilating passages adjacent said surface, and light producingmeans lodged within the box near the open end thereof.

3. A drafting structure comprising a suitable support, an invertedfrusto-pyramidal light box thereon open at the smaller end and providedat the larger end with a light transmitting working surface and withventilating passages adjacent such surface, and light emitting meanswithin the box adjacent the open end thereof.

4. A drafting structure comprising abasic member, a frusto-pyramidallight boxhinged at the smaller end to the basic member and at the largerend provided with a light transmitting working surface, andadjustableholding means between the basic member and the box for holdingsaid box with its working surface level or tilted, as desired.

5. A drafting structure comprising a basic member, a frusto-pyramidallight box having its larger provided with a light transmitting workingsurface, hinge connections between one side of the small end of the boxand the basic member, adjustable holding means between the basic memberand the box for maintaining the box with its surface level or inclined,as desired, and light emitting means within the box at the smaller endthereof.

6. A drafting structure comprising a basic member, a frusto-pyramidallight box having its smaller end 'open and its larger end provided witha light transmitting working surface, and with ventilating openingsadjacent said surface, hinge connections between one side of the smallend of the box and the basic member, adjustable holding means betweenthe basic member and the box for maintaining the box with its surfacelevel or inclined as desired, and electric lamps within the box at thesmall end thereof.

7. A drafting structure including a light box open at one end and at theother end provided with a light transmitting working surface, said boxbeing also provided with ventilating openings adjacent the workingsurface and with means for closing the ventilating openings to anydesired extent.

8. A drafting structure comprising a basic member, a frusto-pyramidallight box at the larger end havingalight transmitting working surface,hinge connections between one edge of the smaller end of the box and thebasic member, link connections between the box and the basic member,said links having elongated slots and the basic member being providedwith clamp screws traversing the slots for the holding of the box withits surface level or tilted at will, and electric lamps within the boxat the smaller end thereof.

9. A drafting structure comprising a supporting frame having divergentlegs at opposite ends, a frusto-pyramidal light box having the smallerend open and the larger end closed by a light transmitting memberforming part of the working surface of the structure, the box alsohaving ventilating openings adjacent the Working surface, movable cutoff members for closing the ventilating openings to any desired extentand carried by the box, electric lamps carried by the smaller end of thebox, the said box having its inner walls covered with light difi'usingmaterial, hinge connections between one side of the smaller end of thebox and one side of the supporting frame, and adjustable holding meansbetween the box and the supporting. frame for holding said box with itsworking surface level or inclined at will.

10. In a drafting table of the class described, the combination of abase, a light transmitting table top, a light box under the table top, alight producing means centrally disposed within the lower end of the boxto uniformly illuminate the said light transmitting table top, and aventilating opening in said li ht box immediately adjacent said lightproducing means, substantially as described.

11. In a drafting table of the class described, the combination of abase,'a light transmitting table top, a light boxof symmetricalpyramidal shape under the table top, a light producing means centrallylocated in the lower end of the light box to illuminate said lighttransmitting table top, a Ventilating opening in said box' adjacent saidlight producing means, and a ventilat ing opening in said light boxadjacent the table top, thus permitting the circulation of air throughsaid first mentioned ventilating opening up through the light -.boxfandout through the other ventilating opening, substantially as described.

12. In a drafting table of the class described, the combination of abase, a light transmitting-table top, a light box of substantiallysymmetrical pyramidal shape under said table top, the inner walls ofwhich have a light diffusing surface, and a light producing meanscentrally located within the lowerend of said light box to illuminatethe said light transmitting table top.

In testimony that I claim the foregoing.

as my own, I have hereto affixed my signature in the presence of twowitnesses.

- CHARLES B. ULRICH.

Vitnesses:

PEARL KENDALL, DANIEL FISHER.

